1. Field of the Invention
The present invention relates to a wireless local area network (WLAN) system, and more particularly, to a method for transmitting a data frame by a sender in a WLAN system and an apparatus for supporting the same.
2. Related Art
Recently, various wireless communication technologies are under development in accordance with the advancement of an information communication technology. Among them, a wireless local area network (WLAN) is a technique of wirelessly accessing the Internet at homes, in offices, or in a particular service providing area, using portable terminals such as personal digital assistants (PDAs), lap top computers, portable multimedia players (PMPs), and the like, based on a radio frequency technology.
As a technology specification that has been relatively recently legislated in order to overcome a limitation in a communication speed that has been pointed out as a weak point in the WLAN, there is the IEEE 802.11n. An object of the IEEE 802.11n is to increase a speed and reliability of a wireless network and extend an operating distance of the wireless network. More specifically, the IEEE 802.11n is based on a multiple input and multiple output (MIMO) technology in which multiple antennas are used at both of a transmit end and a receive end in order to support a high throughput (HT) having a maximum data processing speed of 540 Mbps or more, minimize a transmission error, and optimize a data rate.
As the supply of the WLAN is activated and applications using the WLAN is diversified, the necessity for a new WLAN system for supporting a throughput higher than a data processing speed supported by the IEEE 802.11n has recently increased. The next generation WLAN system supporting a very high throughput (VHT) is the next version of the IEEE 802.11n WLAN system and is one of the IEEE 802.11 WLAN systems that have been newly suggested recently in order to support a data processing speed of 1 Gbps or more in a MAC service access point (SAP).
The next generation WLAN system supports transmission in a multi-user multiple input multiple output (MU-MIMO) scheme in which a plurality of non-AP STAs simultaneously accesses wireless channels in order to efficiently use the wireless channels. According to the MU-MIMO transmission scheme, an AP may simultaneously transmit frames to one or more MIMO paired station (STA).
The next generation WLAN system may support 80 MHz, contiguous 160 MHz, non-contiguous 80+80 MHz, and a channel bandwidth higher than the above-mentioned bandwidth in order to support a higher throughput. In addition, the next generation WLAN system supports a transceiving scheme of a duplicated data unit. In this case, the next generation WLAN system may support dynamic bandwidth operation. In connection with functions that may be supported in the next generation WLAN system as described above, a method for processing data that a transmit STA is to transmit and transmitting the data, a method for normally receiving the transmitted data in a receive STA, and an apparatus for supporting the same, has been demanded.